[Mike Feudo]

Re: distributor timing help - initial/total advance

You don't worry about the vacuum advance when you calculate the total. At WOT(very low manifold vacuum) the vacuum advance does nothing. 40 deg at idle with the vacuum advance is fine as long as you don't get any surging at real light throttle.

 

[Mike Feudo]

Re: distributor timing help - initial/total advance

If it doesn't surge it will be fine. you won't get anywhere near 19in of vac. when there is enough load on the motor to cause detonation